1. Field of the Invention
The present invention relates to the electromechanical battery, and more specifically, it relates to an improvement in the windings that couple energy into and out of the rotor of an electromechanical battery where the improvement provides power in the event of a utility main power failure.
2. Description of Related Art
A critical problem for many sensitive electronic devices, including modern computer systems, is to protect them against irregularities in the power delivered to them from utility mains. This problem has two aspects. The first problem is upward voltage transients that can upset the electronics systems, e.g., in a computer. The second, and more serious one, is when the supply line voltage drops below normal, or even fails completely for some extended period. While the first problem can be addressed, at least partially, through surge-suppressors, the second one requires a viable degree of isolation from power xe2x80x9cbrown outs.xe2x80x9d Outright failures can only be addressed by providing a very sophisticated system that eliminates even fractional-cycle drops in providing power to currently used complicated electronic systems, even including systems using superconductor magnet energy storage and complicated electronic switching techniques.
It is an object of the present invention to provide an improvement to an electric machine such as the electromechanical battery, where the improvement provides both complete isolation from upward voltage surges and transientless power in the event of a utility main power failure.
It is another object of the present invention to replace the normal stator windings of the generator/motor of an electromechanical battery with two orthogonal sets of windings where each set of windings is decoupled from each other electrically.
The invention is an improvement to the electro-mechanical (E-M) battery. In the E-M battery design that employs a fiber composite rotor, the inner surface carries an array of permanent magnets. The rotating field from this array then couples inductively to windings located inside the array.
In the present invention, a modification is made to the windings that couple energy into and out of the rotor. The normal stator windings of the generator/motor have been replaced by two orthogonal sets of windings. Because of their orthogonality, they are decoupled from each other electrically, though each can receive (or deliver) power flows from the rotating field produced by the array of permanent magnets.
Power is delivered to a frequency converter that converts the utility mains frequency to a variable frequency voltage synchronized to the rotation speed of the flywheel of the electromechanical battery. When the system is first activated the frequency converter circuitry will energize one set of two orthogonal windings to bring the flywheel system up to its normal operating speed, at which point it will store enough kinetic energy to operate a computer system during power failure. The second set of windings then will be coupled to another frequency converter system using rectifiers and an inverter to convert power to the ac frequency needed by the computer system. For redundancy, another E-M battery may be connected to the frequency converter, so that failure of either E-M module, or its disconnection for maintenance, would not result in power interruption.